Stent thrombosis is a rare, but serious, complication of percutaneous coronary intervention and is associated with severe morbidity and mortality. In addition to clinical and pathological studies, intravascular imaging has advanced our understanding of the mechanisms underlying stent thrombosis. In particular, intravascular imaging has been used to study stent underexpansion, malapposition, uncovered struts, and neoatherosclerosis as risk factors for stent thrombosis. Intravascular ultrasonography and optical coherence tomography can be used to guide stent implantation and minimize the risk of stent thrombosis. Additionally, optical coherence tomography offers the unique potential to tailor treatment of stent thrombosis to address the specific mechanism underlying the thrombotic event. Bioresorbable stent technologies have been introduced with the goal of further reducing the incidence of stent thrombosis, and intravascular imaging has had an integral role in the development and assessment of these new devices. In this Review, we present insights gained through intravascular imaging into the causes of stent thrombosis, and the potential utility of intravascular imaging in the optimization of stent deployment and treatment of stent thrombosis events.